Inverter Bypass Option; Minimum And Maximum Cfm - Lennox LGH180H Installation Instructions Manual

Set Minimum Position 2
Use the same menu in the Unit Controller to set "Min OCP
Blwr High" for the blower CFM above the "midpoint" CFM.
When navigating into this menu, the Unit Controller will
bring on the corresponding blower speed and allow
damper position adjustment.
SETTINGS > RTU OPTIONS > DAMPER > MIN
DAMPER POSITION BLOWR ON HIGH = X.X%
Measure the intake air CFM. If the CFM is lower than the
design specified CFM for ventilation air, use the Unit
Controller to increase the damper percent open. If the
CFM is higher than specified, decrease the damper
percent open.
Note - Intake air CFM can also be determined using the
outdoor air temperature, return air temperature and
mixed air temperature. Refer to the economizer or
outdoor air damper installation instructions.
E-Inverter Bypass Option
The supply air inverter is factory-set to by-pass the
inverter manually. To by-pass the inverter and operate the
blower in the constant air volume mode, use the following
Unit Controller menu and set to "engaged":
SETTINGS > RTU OPTIONS > BLOWER > VFD
BYPASS
To configure the unit to by-pass the inverter automatically,
use the following Unit Controller menu.
SETUP > INSTALL
Press SAVE until the menu reads:
CONFIGURATION ID 1
th
Change the 6 character position to A for automatic
bypass option.
Press SAVE
Caution - Units not equipped with an inverter will have the
th
6 character set to N, indicating the inverter is not
bypassed. The blower motor could be damaged and/or
result in product or property damage if the setting is
changed to automatic or manual.
LGH/LCH156, 180, 210, 240, 300S

MINIMUM AND MAXIMUM CFM -

156, 180H, 210, 240H, 300S
Gas Heat Minimum CFM
Unit
LGH156-300S
LGH180-300S
Electric Heat Minimum CFM
Unit
LCH156
LCH180-300S
Cooling Minimum CFM - 220 CFM/ton
Unit
LGH/LCH156 Low, Med. Low, Med., Med. High
LGH/LCH180 Low, Med. Low, Med., Med. High
LGH/LCH210 Low, Med. Low, Med., Med. High
LGH/LCH240 Low, Med. Low, Med., Med. High
LGH/LCH300S Low, Med. Low, Med., Med. High
Cooling Minimum CFM - 280 CFM/ton
Unit
LGH/LCH156
LGH/LCH180
LGH/LCH210
LGH/LCH240
LGH/LCH300S
Smoke and Ventilation Minimum CFM - 150 CFM/ton
Unit
LGH/LCH156
LGH/LCH180
LGH/LCH210
LGH/LCH240
LGH/LCH300S
Heating and Cooling Maximum CFM - 480 CFM/ton
Unit
LGH/LCH156
LGH/LCH180
LGH/LCH210
LGH/LCH240
LGH/LCH300S
Page 44
TABLE 23
Gas Heat Size
Airflow CFM
Low, Std. Med.
High
Heat Size (kW)
Airflow CFM
All
All
Blower Speed
Airflow CFM
Blower Speed
Airflow CFM
High
High
High
High
High
Not Applicable
Airflow CFM
NA
NA
NA
NA
NA
Blower Speed
Airflow CFM
High
High
High
High
High
4500
5125
5200
6000
2860
3300
3850
4400
5500
3640
4200
4900
5600
7000
1950
2250
2625
3000
3750
6240
7200
8400
9600
12000